--- title: "Best free email APIs in 2026" description: "Free email APIs ranked by what the free plan really gives you: monthly volume, daily caps, domains, inbound and marketing, and the price of the first paid step." url: https://www.unitpost.com/best/free-email-apis section: Roundups updated: 2026-11-02 --- # Best free email APIs in 2026 Unitpost has the best free email API plan for most apps: 5,000 emails a month with no card, plus the API, SMTP relay, webhooks, inbound email and marketing campaigns on the free plan. Brevo sends more for free (300 a day), Resend gives 3,000 a month, and Postmark's free plan never expires but holds 100 emails. > Updated 2026-11-02. We make Unitpost, and it is on this list. Every score has a reason and the weights are published below, so you can re-rank it for your own needs. ## At a glance | # | Product | Best for | Free plan | Score | | --- | --- | --- | --- | --- | | 1 | Unitpost | a free plan you can launch on | 5,000 emails a month, 200 a day, no card | 4.6 | | 2 | Brevo | the most free emails | 300 emails a day | 4.0 | | 3 | Resend | a developer-first free tier | 3,000 emails a month, 100 a day | 3.8 | | 4 | Loops | SaaS teams that also send campaigns | 1,000 contacts and 4,000 sends a month | 3.2 | | 5 | MailerSend | a cheap first paid plan | 500 emails a month, card required | 3.1 | | 6 | Postmark | testing before you pay | 100 emails a month | 2.9 | | 7 | Mailgun | trying a high-volume API | 100 emails a day on one domain | 2.8 | ## 1. Unitpost Best for a free plan you can launch on. 5,000 emails a month with the whole product switched on: API, SMTP, webhooks, inbound and campaigns. The first paid step is $10 a month. Pros: - 5,000 emails a month, no card, no expiry - Inbound email, campaigns and the MCP server on the free plan - Up to 5 sending domains on free - $10 a month for 20,000 emails when you outgrow it Cons: - A 200-a-day cap on free - One team seat and 7 days of logs on free Free plan: 5,000 emails a month, 200 a day, no card. Paid from: $10 a month for 20,000 emails. Priced by: emails sent. Website: https://www.unitpost.com ## 2. Brevo Best for the most free emails. The biggest free volume here, inside a marketing suite with a transactional API and SMTP relay. Free sending starts once Brevo approves the account. Pros: - 300 emails a day, about 9,000 a month - API, SMTP relay and campaigns on the free plan - Starter from $9 a month Cons: - Sending starts after account approval - The API serves a marketing suite first Free plan: 300 emails a day. Paid from: $9 a month for 5,000 emails. Priced by: emails sent. Website: https://www.brevo.com ## 3. Resend Best for a developer-first free tier. A modern API with 3,000 free emails a month, inbound email and 1,000 marketing contacts on free. The daily cap is 100. Pros: - A modern API with clear errors and many SDKs - Inbound email and 1,000 marketing contacts on free - Three domains on the free plan Cons: - Capped at 100 emails a day - One webhook endpoint on free Free plan: 3,000 emails a month, 100 a day. Paid from: $20 a month for 50,000 emails. Priced by: sends and contacts. Website: https://resend.com ## 4. Loops Best for SaaS teams that also send campaigns. Email for SaaS products with campaigns, workflows and transactional sends on one free plan, priced by contacts once you grow. Pros: - Campaigns, workflows and transactional email on free - 4,000 sends a month - An official hosted MCP server Cons: - At most 1,000 subscribed contacts on free - A Loops footer on free, and transactional sends need a published template Free plan: 1,000 contacts and 4,000 sends a month. Paid from: $49 a month for up to 5,000 contacts. Priced by: contacts. Website: https://loops.so ## 5. MailerSend Best for a cheap first paid plan. A transactional email API with a small free plan and the cheapest first paid step here. Free covers the API and SMTP on one domain. Pros: - API and SMTP on the free plan - Hobby is $7 a month for 5,000 emails - An official hosted MCP server Cons: - 500 emails a month on free, and the free plan needs a card - One domain, one template and 100 API requests a day on free Free plan: 500 emails a month, card required. Paid from: $7 a month for 5,000 emails. Priced by: emails sent. Website: https://www.mailersend.com ## 6. Postmark Best for testing before you pay. A developer plan that never expires, for testing Postmark's well-regarded transactional sending. It holds 100 emails a month. Pros: - Never expires, no overages - API, SMTP and inbound on the free plan - A strong deliverability record when you upgrade Cons: - 100 emails a month - Bulk email isn't on the free plan Free plan: 100 emails a month. Paid from: $15 a month for 10,000 emails. Priced by: emails sent. Website: https://postmarkapp.com ## 7. Mailgun Best for trying a high-volume API. A permanent free plan of 100 emails a day on one domain, on an API built for volume. Logs last a day on free. Pros: - 100 emails a day, permanently - One inbound route on free - Proven at very high volume when you grow Cons: - One domain and one day of logs on free - HTTP Basic auth instead of a bearer token Free plan: 100 emails a day on one domain. Paid from: $15 a month for 10,000 emails. Priced by: emails sent. Website: https://www.mailgun.com ## Scores | Product | Free volume (30%) | What's included (25%) | No strings (15%) | Developer experience (20%) | First paid step (10%) | Total | | --- | --- | --- | --- | --- | --- | --- | | Unitpost | 4 | 5 | 4 | 5 | 5 | 4.6 | | Brevo | 5 | 4 | 3 | 3 | 4 | 4.0 | | Resend | 3 | 4 | 4 | 5 | 3 | 3.8 | | Loops | 3 | 4 | 3 | 3 | 2 | 3.2 | | MailerSend | 2 | 3 | 3 | 4 | 5 | 3.1 | | Postmark | 1 | 3 | 5 | 4 | 3 | 2.9 | | Mailgun | 3 | 2 | 3 | 3 | 3 | 2.8 | ## How we scored This list is for developers who need app email at no cost: side projects, prototypes and early products. What matters to them: how much the free plan sends, what it includes, the strings attached, and what the first paid step costs once the app grows. - **Free volume (30%).** Emails a month on the free plan, for good, and how tight the daily cap is. - **What's included (25%).** API and SMTP, domains, webhooks, inbound and marketing email on the free plan. - **No strings (15%).** It never expires and needs no card, approval or footer. - **Developer experience (20%).** A clear REST API, current SDKs, readable errors and docs. - **First paid step (10%).** A cheap first paid plan that grows with sends. Each product gets 1 to 5 per criterion; the total is the weighted mean. ### Why Unitpost scored 4.6 - Free volume: 4/5. 5,000 emails a month, capped at 200 a day. - What's included: 5/5. API, SMTP, webhooks, inbound, campaigns and the MCP server all work on free. - No strings: 4/5. No card and no expiry; one seat and 7 days of logs. - Developer experience: 5/5. Bearer-token REST API, nine SDKs, a CLI and an MCP server, with idempotency keys on sends. - First paid step: 5/5. $10 a month for 20,000 emails, priced by sends. Checked 2026-11-02 against https://www.unitpost.com/pricing, https://www.unitpost.com/sms, https://registry.npmjs.org/unitpost. ### Why Brevo scored 4.0 - Free volume: 5/5. 300 emails a day, the most of any free plan here. - What's included: 4/5. API, SMTP relay and campaigns are on the free plan. - No strings: 3/5. Permanent, but sending starts once Brevo approves the account. - Developer experience: 3/5. A full API and SMTP relay, shaped by the marketing suite rather than built for developers first. - First paid step: 4/5. Starter from $9 a month, sized by email volume. Checked 2026-11-02 against https://www.brevo.com/pricing/, https://developers.brevo.com/docs/mcp-protocol, https://help.brevo.com/hc/en-us/articles/7959631848850, https://help.brevo.com/hc/en-us/articles/360021533839, https://registry.npmjs.org/@getbrevo/brevo. ### Why Resend scored 3.8 - Free volume: 3/5. 3,000 emails a month, capped at 100 a day. - What's included: 4/5. API, SMTP, inbound and broadcasts to 1,000 contacts; one webhook. - No strings: 4/5. A permanent plan; limits sit on domains and webhooks. - Developer experience: 5/5. The API many newer providers copy, with SDKs across most languages. - First paid step: 3/5. Pro is $20 a month for 50,000 emails; marketing contacts are a second plan. Checked 2026-11-02 against https://resend.com/pricing, https://resend.com/migrate, https://resend.com/docs/dashboard/receiving/introduction, https://github.com/resend/mcp-send-email, https://resend.com/docs/send-with-smtp, https://resend.com/docs/api-reference/api-keys/create-api-key, https://registry.npmjs.org/resend, https://resend.com/docs/dashboard/webhooks/retries-and-replays. ### Why Loops scored 3.2 - Free volume: 3/5. 4,000 sends a month, to at most 1,000 subscribed contacts. - What's included: 4/5. Transactional API, SMTP, campaigns and workflows on free. - No strings: 3/5. Free emails carry a Loops footer. - Developer experience: 3/5. A clean API, but transactional sends must use a template published in Loops. - First paid step: 2/5. Growth is $49 a month, priced by contacts. Checked 2026-11-02 against https://loops.so/pricing, https://loops.so/docs/transactional, https://loops.so/docs/mcp-server. ### Why MailerSend scored 3.1 - Free volume: 2/5. 500 emails a month. - What's included: 3/5. API and SMTP on one domain, with one template. - No strings: 3/5. A permanent free plan, but it needs a card, and limits domains, templates and API requests. - Developer experience: 4/5. A modern REST API, SMTP and an official MCP server. - First paid step: 5/5. Hobby is $7 a month for 5,000 emails. Checked 2026-11-02 against https://www.mailersend.com/pricing, https://developers.mailersend.com/mcp, https://www.mailersend.com/help/smtp-relay, https://www.mailersend.com/features/inbound-emails, https://developers.mailersend.com/api/v1/webhooks.html, https://registry.npmjs.org/mailersend, https://developers.mailersend.com/api/v1/inbound. ### Why Postmark scored 2.9 - Free volume: 1/5. 100 emails a month. - What's included: 3/5. API, SMTP and inbound; no bulk sending. - No strings: 5/5. The developer plan never expires and has no overages. - Developer experience: 4/5. A mature, well-documented API with official libraries. - First paid step: 3/5. Basic is $15 a month for 10,000 emails. Checked 2026-11-02 against https://postmarkapp.com/pricing, https://postmarkapp.com/migration-guides, https://postmarkapp.com/lp/mcp, https://postmarkapp.com/developer/user-guide/send-email-with-smtp, https://registry.npmjs.org/postmark, https://postmarkapp.com/developer/webhooks/inbound-webhook. ### Why Mailgun scored 2.8 - Free volume: 3/5. 100 emails a day, about 3,000 a month. - What's included: 2/5. One domain, one inbound route and one day of logs. - No strings: 3/5. Permanent, but one day of logs makes debugging hard. - Developer experience: 3/5. A capable API on HTTP Basic auth, with a surface shaped by long history. - First paid step: 3/5. Basic from $15 a month for 10,000 emails. Checked 2026-11-02 against https://www.mailgun.com/pricing/, https://www.mailgun.com/resources/guides/migrating-from-sendgrid-to-mailgun-email-api/, https://documentation.mailgun.com/docs/mailgun/mcp, https://documentation.mailgun.com/docs/mailgun/user-manual/sending-messages/send-smtp, https://registry.npmjs.org/mailgun.js, https://documentation.mailgun.com/docs/mailgun/user-manual/receive-forward-store/receive-http. ## FAQ ### Which email API has the biggest free plan? Brevo's, at 300 emails a day (about 9,000 a month). Unitpost's is 5,000 a month with no card and includes inbound and campaigns; Resend's is 3,000 a month at 100 a day. ### Is there a free SendGrid plan? No. SendGrid retired its free plan in 2025 and offers a 60-day trial at 100 emails a day. Amazon SES has no SES free tier either; new AWS accounts get credits instead. ### What should a free email plan include? Enough volume for your real traffic, your own sending domain, webhooks for bounces, and logs long enough to debug. Inbound email and marketing campaigns on the same plan save a second tool later. ## Related - [Best transactional email services in 2026](https://www.unitpost.com/best/transactional-email-services): Transactional email services ranked for receipts, password resets and sign-in codes: deliverability, the API, the free plan, scale and the first paid step. - [Best email APIs for Node.js in 2026](https://www.unitpost.com/best/email-apis-for-nodejs): Email APIs ranked for Node.js and TypeScript: the official SDK and its types, the API, the free plan, deliverability and the first paid step, from npm data. - [Best inbound email parsing services in 2026](https://www.unitpost.com/best/inbound-email-parsing): Inbound email parsing services ranked: the parsed message and its verdicts, how deliveries are signed and retried, and receiving on the free plan.